Mandibular protrusion is usually caused by mandibular protrusion, which is mainly corrected and treated by surgery, and early preventive treatment is also available. Surgical procedures include sagittal split osteotomy of the ascending mandibular branch, vertical osteotomy of the ascending mandibular branch, and subapical osteotomy of the anterior mandibular root. It is also necessary to determine whether to perform preoperative and postoperative orthodontics according to the type and degree of malocclusion. Early prevention can be done by using orthodontic appliances during the period of milk teeth to inhibit the anterior antomandibular teeth. Frank III braces can be used during the replacement period. For patients with maxillary hypoplasia, a maxillary expansion device can be used for forward traction for orthodontic prophylaxis. If you find protruding lower jaw, you should consult a doctor in time and treat it under the doctor’s guidance, do not treat it without authorization to avoid delaying the condition. Pay attention to rest on weekdays, quit smoking and drinking, and keep oral hygiene clean.